detection (and not build time GL headers)
- add a new debug channel for hardware vertex shaders
- hardware VS "compiler" fixes:
  -> special case for address registers (MOV must be replaced by ARL)
  -> add line numbers to trace (better to find why NVidia drivers complains)
  -> one parse to determine temporary and address registers needs
    (@todo: check GL limits)
  -> remove duplicate traces from Generic ParseProgram